腹部平片不易显影的尿结石是（）。

A.磷酸盐结石

B.草酸盐结石

C.碳酸盐结石

D.尿酸结石

E.混合结石

.—Jim!Did you have a good time at the party?

—Yes,but I really _________ have because I had a lot of work to do.

A．needn’t

B．mustn’t

C．shouldn’t

D．couldn’t